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Early colonoscopy for acute lower GI bleeding fails to improve diagnostic yield or reduce rebleeding rate

Key clinical point: Early colonoscopy did not improve stigmata identification or reduce rebleeding rates in patients admitted for acute lower gastrointestinal bleeding.

Major finding: Stigmata of recent hemorrhage were identified in 21.5% and 21.3% of patients undergoing early and elective colonoscopy, respectively (P = .967). Rates of 30-day rebleeding were not statistically different between groups.

Study details: Randomized multicenter trial of 162 adult patients with moderate to severe hematochezia or melena within 24 hours of admission.

Disclosures: Authors reported grant funding from the Japanese Gastroenterological Association and disclosures related to Takeda, AstraZeneca, Zeria, Daiichi-Sankyo, and EA Pharma.


Niikura R et al. Gastroenterology. 2019. doi: 10.1053/j.gastro.2019.09.010.


When to perform colonoscopy for the evaluation of acute lower gastrointestinal bleeding (LGIB) is controversial. Multiple observational studies, three small, single center randomized controlled trials, and several meta-analyses have produced mixed results. Therefore, a large, multicenter trial is of high priority.

This study by Niikura et al. is the largest and first multicenter trial on this topic. The authors found no difference between the early vs. elective colonoscopy arms in the primary outcome, identification of stigmata of recent hemorrhage (SRH). SRH is a surrogate outcome; however, previous studies have found SRH to be predictive of rebleeding, and any decrease in rebleeding would likely be due to endoscopic treatment of these lesions. Furthermore, although the study was not powered to detect differences in clinical outcomes such as rebleeding, the 95% confidence interval suggests at most a 1.4% decrease in rebleeding with early colonoscopy. It is possible that early colonoscopy is beneficial in certain patient populations or in expert hands. However, in subgroup analyses there was no benefit for early colonoscopy in patients with severe bleeding, a diverticular source, or a colonoscopy performed by an expert.

Overall, the results suggest that in most patients presenting with acute LGIB, we do not need to perform colonoscopy within 24 hours of admission. However, the mean time to colonoscopy in the elective group was 41 hours from presentation. Therefore, colonoscopy should be performed on a next available basis. Further delays add unnecessary hospital days and increase cost of care. Future studies are needed to identify alternative ways to improve outcomes in LGIB, define the management of unstable patients with acute LGIB, and perfect the approach to endoscopic hemostasis in the colon.

Lisa L. Strate, MD, is professor of medicine, University of Washington, and section chief, gastroenterology, Harborview Medical Center, Seattle.